Imported Upstream version 16.04

[deb_dpdk.git] / lib / librte_sched / rte_sched_common.h

diff --git a/lib/librte_sched/rte_sched_common.h b/lib/librte_sched/rte_sched_common.h
new file mode 100644 (file)
index 0000000..8920ade
--- /dev/null
+++ b/lib/librte_sched/rte_sched_common.h
@@ -0,0 +1,129 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ *   All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef __INCLUDE_RTE_SCHED_COMMON_H__
+#define __INCLUDE_RTE_SCHED_COMMON_H__
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <sys/types.h>
+
+#define __rte_aligned_16 __attribute__((__aligned__(16)))
+
+static inline uint32_t
+rte_sched_min_val_2_u32(uint32_t x, uint32_t y)
+{
+       return (x < y)? x : y;
+}
+
+#if 0
+static inline uint32_t
+rte_min_pos_4_u16(uint16_t *x)
+{
+       uint32_t pos0, pos1;
+
+       pos0 = (x[0] <= x[1])? 0 : 1;
+       pos1 = (x[2] <= x[3])? 2 : 3;
+
+       return (x[pos0] <= x[pos1])? pos0 : pos1;
+}
+
+#else
+
+/* simplified version to remove branches with CMOV instruction */
+static inline uint32_t
+rte_min_pos_4_u16(uint16_t *x)
+{
+       uint32_t pos0 = 0;
+       uint32_t pos1 = 2;
+
+       if (x[1] <= x[0]) pos0 = 1;
+       if (x[3] <= x[2]) pos1 = 3;
+       if (x[pos1] <= x[pos0]) pos0 = pos1;
+
+       return pos0;
+}
+
+#endif
+
+/*
+ * Compute the Greatest Common Divisor (GCD) of two numbers.
+ * This implementation uses Euclid's algorithm:
+ *    gcd(a, 0) = a
+ *    gcd(a, b) = gcd(b, a mod b)
+ *
+ */
+static inline uint32_t
+rte_get_gcd(uint32_t a, uint32_t b)
+{
+       uint32_t c;
+
+       if (a == 0)
+               return b;
+       if (b == 0)
+               return a;
+
+       if (a < b) {
+               c = a;
+               a = b;
+               b = c;
+       }
+
+       while (b != 0) {
+               c = a % b;
+               a = b;
+               b = c;
+       }
+
+       return a;
+}
+
+/*
+ * Compute the Lowest Common Denominator (LCD) of two numbers.
+ * This implementation computes GCD first:
+ *    LCD(a, b) = (a * b) / GCD(a, b)
+ *
+ */
+static inline uint32_t
+rte_get_lcd(uint32_t a, uint32_t b)
+{
+       return (a * b) / rte_get_gcd(a, b);
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __INCLUDE_RTE_SCHED_COMMON_H__ */